The art recognizes several methods for eliminating the waxy component(s) of waxy feeds, generally referred to as dewaxing. Solvent refining was, and is still currently, a method by which wax is removed from waxy feedstocks. The use of solvent is both cumbersome and expensive, because of the volume to feed to be processed, and the inherent expense of solvent.
Catalyst cracking and hydrocracking treatments may be used to reduce the wax content of feedstocks. The wax content of feedstocks is attributable to long chain unbranched and slightly branched aliphatics. Accordingly, catalytic cracking (and hydrocracking) of the wax components reduce the liquid volume of product vis-a-vis that of the feed. Moreover, alteration of other components of the feed occurs.
The problems which inhere in those dewaxing processes are in large part due to the complexity of the molecular constitution of the feeds. Accordingly, empirical considerations control dewaxing processing techniques.